Thermostat



1,455fifi3 F. W. ROBERTSHAW ET AL THERMOSTAT Filed Sept. 10, 1921 2 Sheets-Sheet 2 May 15, 1923.

I ENTOR5 Patented c.3115, 1-923. v

GREENSBURG,

PENNSYLVANIA.

THERMOSTAT.

' Application filed September T all whom it may concern:

Be it known that we, FREDERICKLl/V. Ronnn'rsHAw and GEORGE A. Ronnn'rsHAw, both citizens of the United States residing, respectivelyyat Pittsburgh, Allegheny County, Pennsylvania, and Greensburg, VVcstmoreland County, Pennsylvania, have invented a new and useful Improvement in ,Thermo-- stats, of which the following is a full, clear, and exact description. 1

The present invention relates broadly to thermostats, and more particularly to thermostats adapted for use in connection with ovens and the like, although its use in this respect is not limited.

An important object of the invention is to provide a thermostatically operated valve the arts of which are readily accessible for cleaning and may be removed Without affectingthe valve setting.

Another object of the invention is to provide a thermostat in which it is impossible to lose the original setting during ordinary use thereof.

Still another object of the invention is to provide a thermostatically operated valve having means on one end for setting the valve and means on the opposite end for correcting said setting.

A further object of the invention is to provide a device of the character described, capable of being operatively set at any desired temperature from a distance.

The foregoing and other objects of the present invention, together with their attendant advantages, will be apparent as the invention becomes better understood by reference to the accompanying specification and drawings forming a part thereof, it being premised that changes may be made in the various details and the manner of operation within the scope of the appended claims without departing from the spirit of the invention.

Figure 1 is a longitudinal sectional view through a valve and its operating thermostat constructed in accordance with the present invention;

Fi ure2 is an end view of the construction illustrated in Figure 1;

Figure 3 is a top lan view of a portion of the construction lustrated in Figure 1;

Figure 4: is a detail view of the spacing and holding bracket;

Figure 5 is a view,

corresponding to Fig- 10, 1921. Serial No. 499,599. I

A.- RQBERTSHAW, OF

ure 1, illustrating a modified form of thermostatically operated valve; and

Figure 6 is an end view of the construction illustrated in Figure 5. Referring more particularly to the drawlngs, there is illustrated a supporting body which may be in the form of a valve casing 1 having an inlet connection 2 and an outlet connection 3,- and constituting part of a controlling device. Intermediate the ports of these connections the casing is provided with a seat 4: of any usual construction adapted to cooperate with a valve 5 for closing the connection between the inlet and outlet ports. The valve 5 is normally urged in the direction of the seat 4 by a suitable spring 6, and may be guided in its movement by a stem 7 formed thereon and extending into a boss 8 projecting inwardly from the casing. Access to the casing is provided by removing the closure 9, thereby permitting the parts of the valve to be removed at will for cleaning or replacing, as may be necessary. The inlet and out-let ports may be connected by a small bypass or bleed opening of usual construction, controlled by a regulating screw 10, thereby permitting a pilot flame to be maintained at all times.

Extending rearwardly from. the casing 2 is a projection 11 having its outer surface threaded. The thread in the present construction is preferably of comparatively steep pitch and may beveither a. single or double thread, as desired. Cooperating therewith is a revolving couple or adapter 12 having one end threaded to cooperate with the threaded projection 11 and having its opposite end provided with a standard thread to receive the reduced threaded end 13 of the thermostat expanding element 1 1. As is usual in constructions of this char.- acter, the member 14 may be scored or roughened oxer its entire surface and blackened to' facilitate the absorption of heat thereby. a

Located within the expansible member 14 is a non-expansiblemember 15 of suitable material' abutting against a separate pin 16 in alinement with the valve stem 7 and forming a gas tight sealed joint between the valve casing and the interior of the element 14. At its opposite end the non-expansible jelement 15 cooperates with a screw plug 17 the purpose of which will be more fully \pointed out hereinafter.

the temperature of which it is desired to the valve casing 1-by reason of the action of' the threadedprojection 11. Tlh's movement the graduations 20 on the plate 191 'control. A portion of the oven wall 18 is illustrated in the drawings.

In installing the present thermostat, it will be apparent that the gas connections determine the position of the valve casing 1. Located on the exterior of this casing so as to be visible throughout its entire length to the user of the device, is a plate 19 having graduations 20 thereoh which are" marked to indicate different degrees of temperature at which it is desired to maintain the oven. Clamped about the revolving couple 12 is an arm 21 provided with an operating handle 22 and a pointer 23 cooperating wgh y moving the handle 22 it will be ,apparant that the revolving couple 12 is rotated, thereby moving the same toward or away from is amplified by providing a thread of high pitch as set forth. When the thermostatic valve is assembled, the threaded plug 17 is screwed into such a position that the operation of the valve is in accordance with the graduations on the plate 19. Thereafter, the user of the valve may regulate the temperature at which the same operates by the han-, dle 22. The plug 17 therefore provides means for correcting the setting ofthe valve, while the handle 22 provides means for setting the same. In order to increase the range of movement of the revolving couple, to accommodate non-expansible elements of different-lengths, or for other purposes, the revolvingcouple, may have formed therein two or more openings 25; Preferably two such openings are provided, .positioned at diametrically opposite sides of the couple for receiving the inner end of a stud 24 carried by the bracket arm 21. This permits the position of the bracket arm with respect to the couple to be changedduring assembly of the valve, so that the proper reading 7 may be'obtained to within a few degrees, and thereafter the correcting plug 17 is operated to produce an accurate setting.

With a construction of this kind, it will be apparent .that it is impossible to lose the original setting of the valve, as the handle cannot be rotated except through a limited arc-determinedby the connections 2 and 3. Furthermore, the setting of the thermostat is not affected by removing the valve parts as desired.

The inner end of the device may be carried within a bracket 26 adapted to be see cured to the-oven wall or-top to hold the expansible element in spaced relation thereto.

This bracket will be so formed as to permit the desired rotative and longitudinal movement'of the expansible member.

described, and the parts correspondin In Figures 5 and 6, there is illustrate a construction generally similar to that before to parts already referred to are designate by the same reference character with a prime afiixedthereto. In this form of the invention, the valve casing is illustrated as having its inlet and outlet connections 2' and 3' at diametrically opposite sides thereof.

Itwill be apparent however, that the arrangement of these connections is immaterial. In this construction, the valve case ing 1 is provided with an index pointer 23 and the revolving couple 12 carries a pulley 27 secured thereto by a stud 24 and provided with graduations 20 cooperating with the pointer 23. Around the periphery of the pulley is passed a flexible operating cable 28 the opposite ends of which ma carry suitable weights or handles 29 enab ing the pulley 27 to be rotated to set the temperature at which the valve operates, as will be apparent.

Both forms of the invention illustrated provide a constructioninwhich there is a correcting .device'located at one end of the thermostatic valve and a setting device 10- ting and correcting devices being capable of independent manipulation as required.

The advantages of the present invention arise from the construction of the valve and its controlling thermostat in such manner that the valve parts may be removed atwill Without affecting the setting of thethermostat.

cated at the opposite end thereof, the set- Other advantages of the invention arise from th couple provided-between a body carrying the member to be acutated, or the controlling device, and the thermostat.

Further advantages arise from the pro vision .of settingand correcting devices permitting an accurate operation of the thermostatat all times.

I from the v ating with said expansible member for operating the member. on said body, substantially as described.

2. A thermostat, comprising a controlling device having a movable operating member,

an expansible member, a revolving couple connecting one end of said expansible member and said device, a correcting device at the opposite end of said member, and anionexpansible member cooperating. therewith for operating the movable member of the controlling device, substantially as described.

3. A thermostat, comprising a controlling device having a movable operating member, a threaded projection on said device, the threads on said projection having a high pitch, arevolving couple cooperating with said projection, an expansible member carried by said couple, a non-expansible element cooperating therewith for operating the movable member of said device, and means for revolving said couple to vary the temperature at which the device is operated, substantially as described.

4. A thermostat, comprising'a valve casing having inlet and outlet openings, a valve controlling communication between said openings, a threaded projection on said casing, the threads on said projection having a high pitch, a revolving couple in threaded engagement with said projection, a tubular expansible member carried by said couple, a correcting device cooperating with one end of said member, a non-expansible member within said first mentioned member and abutting against said correcting device and said valve for operating the valve,

and means for revolving said couple to change the temperature at which the valve is operated, substantially as described. I

v 5. A thermostat, comprising a tubular expansible member, a non-expansible member located therein, a' correcting device at one end of said expansible member for engagement with said non-expansible member, a valve operatively secured to the opposite end of said expansible member for cooperation with said non-expansible element, and means independent of said correcting device for changing the adjustment between said valve and said non-expansible member, substantially as described.

6. A thermostat, comprising a valve casing having inlet and outlet openings,'a valve controlling communication between said openings, an expansible member, a revolving couple connecting said casing and said member. a non-expansible member cooperating with said expansible member for operating the valve, and means permitting removal of said valve without afiecting the setting of 'the thermostat, substantially as described. 7 5 a 7 A thermostat, comprising a casing having inlet and outlet connections, a removable valve controlling communication between said connections, a removable closure in said casing providing access to said valve, an expansible member, a revolving couple connecting said casing and said member, and a non-expansible member cooperating with said expansible member for operating the\ valve, substantially as described.

couple for varying the temperature at which 1 said device is'opera'ted, and means for indidating the temperature for which the device is set, substantially as described.

9. A thermostat, comprising a valve-casing having inlet and outlet connections, a valve controlling communication between said connections, a threaded projection on said casing, a revolving couple cooperating with said threaded projection, an expansible member carried by said couple, a non-expansible clement cooperating therewith for operating said valve, and means for revolve ing said couple to vary the temperature at which the valve is operated, substantially as described.

10. A thermostat, comprising a valve casing having inlet and outlet openings, a valve controlling communication between said openings, a threaded projection on said casing, a revolving couple in threaded engagement with said projection, a tubular expansible member carried by said couple, a correcting device cooperating with one end of, said member, a non-expansible member within said first mentioned member and abuting against said correcting device and said valve for operating the valve, and means for revolving said couple to change the temperature at which the valve is opera-ted, substantially as described.

11. A thermostat, comprising a controlling device having a movable operating member, an expansible member a revolving couple connecting said device and said expansible member, a non-expansible member, and a separate longitudinally movable pin intermediate said non-expansible member and said device, substantially as described.

12. A thermostat, comprising a casing having inlet and outlet connections, a valve controlling communication between said connections, an expansible member, a revolving couple connecting one end of said member and said casing, a correcting device at the opposite end of said member. a non-expansible member, and a separate packing pin intermediate said non-expansible member and the valve, substantially as described.

13. A thermostat, comprising a valve casing having inlet and outlet connections, avalve controlling communication between said connections, a threaded projection on said casi g, a revolving couple cooperating with said projection, an expansible member carried by said couple, a non-expansible member cooperating therewith, a separate packing pin intermediate said non-expansible member and the valve, and means for revolving said couple to vary the'temperature at which the valve is operated, substantially as described.

14. A thermostat, comprising a valve case ing having inlet and outlet openings, a Valve controlling communication between said openings, an expansible member, a revolving couple connecting said casing and said member. a non-expansible member, a separate packing pin lntermediate said non-expansiblemember and the valve, and means permitting removal of said valve Without affect, ing thesetting of the thermostat, substantially as described.

15. A thermostat, comprising a casing having inlet and outlet connections, a removiable valve controlling communication beconnecting said casing and said member, anon-expansible member, and a separate packing pin intermediate. said non-expansible member and the valve, substantially as described.

16. A thermostat, comprising a controlling device having a movable operating member, an expansible member, arevolving couple connecting said device and said expansible member, a non-expansible member co-operating with said expansible member for operating the movable member of said device, and means permitting removal of the movable member of said device without affecting the setting of the thermostat, substantiallyvas described. J

In testimonywhereof we have hereunto set our hands,

FREDERICK \V. ROB ERTSHAVV. GEORGE A. ROBERTSHAV. 

